Don't feel guilty at all!
Planning a year in advance is a very smart thing to do, especially with a large family.
Going to WDW for the first time can be overwhelming so it's good to break it down into small steps and take your time.
Have you seen the new Art of Animation resort? I bet your kids would LOVE it! I haven't seen the family suites in person yet but all the photos look amazing. I can't imagine a better place to spend a first trip to Disney with a family your size. There are a lot of pics online of the different themes. I'm not sure if you have boys or girls but I know my boys would FLIP for the Cars themed suite.
I think Disney was very smart to create these rooms because it allows families to be together in one area instead of having to split between 2 rooms. The benefit of having the larger eating area and kitchenette makes you feel more at home... here are some pics:
I just grabbed those off a google image search, there are tons more pics of the other themes to check out.
The big difference between the family suite and getting two rooms is you won't get 4 double beds. But by not having all those beds you open up more floor space and have more of a villa type "home away from home" feel.
This thread should be a huge help:
http://disboards.com/showthread.php?t=2966053